Opinion | Brace Yourself for Waves of Coronavirus Infections

More bad news: Case fatality rates have been creeping up, and lethality may be greater than many had expected. Germany was hailed for a death rate of only about 0.5 percent, and South Korea was not much higher; now both have case fatality rates well above 1 percent.

In models of the virus that my colleague Stuart A. Thompson and I published, we used a death rate of 1 percent. But if the South Korean death rate by age is applied to the demography of the United States, the American case fatality rate is about 2 percent, according to Dr. Christopher Murray, the director of the Institute for Health Metrics and Evaluation.

A great majority of the deaths in the United States will have been avoidable. South Korea and the United States had their first coronavirus cases on the same day, but Seoul did a far better job managing the response. The upshot: It has suffered only 174 coronavirus deaths, equivalent to 1,100 for a population the size of America’s.

That suggests that we may lose 90,000 Americans in this wave of infections because the United States did not manage the crisis as well as South Korea did. As of Friday night, the U.S. had already had more than 7,000 deaths.

Third, while we can bend the curve, it will bend back when we relax our social distancing.

This is more bad news, for many people seem to believe that once we get through this grim month or two, the nightmare will be over. But the virus is resilient, and health experts warn that this may be just the first wave of what may be many waves of infections until we get a vaccine sometime in 2021.

Already, Japan after initial success is seeing a surge of infections, while China and South Korea have struggled with imported infections; that seems inevitable as economies restart and travel resumes.

“There’s this biological fact that still in South Korea, the people who haven’t been infected aren’t immune, and as soon as there’s an end to social distancing they’ll be vulnerable again,” noted Dr. Mark Poznansky of Harvard Medical School.